> You were fooling yourself.

I think that's the entire point of his story.

He said he lost 20 pounds, not 20 pounds of fat.

The interesting thing about sugar is that it also causes your body to retain a lot of water. Same with salt.

So losing 20 pounds in a short time is totally possible for someone who is tall.

+1

It's well known that folks who start a low-carb diet can expect to lose about 5lbs in water weight within the first week.

For an average height, the span between the lowest non-over-or-underweight weight and the highest is a lot more than 20 pounds, and being a bit into the overweight range doesn't automatically make you unhealthy either.

chart: http://www.vertex42.com/ExcelTemplates/Images/body-mass-inde...

Don't forget there's a difference between weight from fat and weight from other sources (muscle, bone, water, etc).

If you lift weights, I wouldn't use body mass indexes.

I'm 10 pounds heavier now than I was 3 years ago and I assure you I'm much healthier. So your sweeping generalization is entirely incorrect.

That's not quite correct. The CDC recommends a body fat percentage between 18% to 25%, and it's generally acknowledged that athletes can drop down to around 5%-6% without adverse effects. So, given those numbers, most healthy adults are carrying at least 20 pounds that they could safely lose.

CDC recommends BMI of 18 to 25. Completely different from body fat percentage. 25% body fat is pretty fat. It's a noticeably protruding belly, drooping love handles, and sometimes breast tissue that could be classified as an A-cup. BMI is a pretty poor standard anyway, since it would classify anyone who does body building even recreationally as obese.

Oops, my mistake. I got confused by this table on the WebMD page below which does list 18-25% as an acceptable range for body fat percentage:

http://www.webmd.com/diet/features/body-fat-measurement#2

So my original numbers were actually correct, but instead of the CDC it's the American Council on Exercise, whatever that is. The page before has the CDC recommendations on BMI. I was surprised too that 25% is considered acceptable. I am aware of the difference between BMI and body fat percentage, and that the former is an inaccurate gauge of fitness.

Considering the American Council on Exercise pushes the "Health at Every Size(C)" bullshit I'd never take them seriously. I can't be bothered to go find real studies on the issue but I would have to guess they'd tell you there's an increased risk of health issues at 25% body fat.

Ah ok, I suppose I expected WebMD to rely on better sources of information. I stay around 7-10% body fat and feel good in that range -- the few times I've gone below that I felt lethargic and performed poorly in sports.

WebMD is the buzzfeed of medical knowledge.

I suspect you're not actually at 7-10% body fat, that is ridiculously low. Like just skin and muscle, nothing else. It is physically impossible for most people to go below 7% without some serious drug abuse or eating disorder. Google image search "7% body fat" and see for yourself.

Your numbers are good for males. Often women have issues if they drop to the 5-6% range... missed periods, decreased fertility, hormonal changes, and other such things. Weirdly, some of the same issues people have with anorexia, only to a healthier extreme. I'm pretty sure they recommend women to have at least 9-11% body fat if they are muscular.